It is written in problem statement, that "there are no more than 2 blocks of each color".
But in sample input there is a color matrix
1 2 3
1 1 1
1 1 1
where there are 7 blocks with color 1.
Is everything correct?
Dec '04
Jan '05
I can see that Tomek Czajka solved the problem first.
Congratulations!
I have a question:
Can there be a simpler version of the problem put on SPOJ, where the colors are all different. I think I can solve it then and It could be an easier start for BLOCKS if I could test my ideas on the simpler version.
Best regards,
Adam
Thanks!
Test your ideas theoretically! 
This was a great problem to spend hours thinking about, thanks problemsetters!
Our pleasure , glad you enjoyed solving it.
Perhaps it will be done one day. But there really isn't much to test in the simpler version - if you know you can solve it, then you can .
If you are in doubt, I think that a very simple random test case generator is enough to verify your ideas (I used this code1 for some of the test data). Run with e.g.: echo "20 400 10 0 1 100 " | ./blockgen to obtain a test case for the simpler version of the problem.
